The effects of the ripening period (1, 3, 7, 11, 13 days), nitrite level (45, 70, 120, 170, 195 mg kg(-1)) and heat treatment (30, 40, 60, 80, 90 degrees C) on counts of total aerobic mesophilic bacteria, lactic acid bacteria (LAB) and Micrococcus-Staphylococcus in sucuk were investigated using a central composite rotatable design of response surface methodology. Counts of total aerobic mesophilic bacteria and lactic acid bacteria were increased and counts of Micrococcus-Staphylococcus were significantly decreased during the ripening period (p<0.01). Counts of all bacteria were significantly decreased by the effects of heat treatment (p<0.01). Nitrite had a significant effect on total aerobic mesophilic bacteria. Enterobacteriaceae, moulds, and yeasts were observed only in the first days of the ripening period.